Vacuum cleaner and system operable with AC and DC power sources

ABSTRACT

A vacuum cleaner includes a suction inlet, a motor, and an impeller connected to the motor and operable to generate suction through the suction inlet upon operation of the motor. The vacuum cleaner further includes a power connector mounted to the vacuum cleaner and selectively connectable to a direct current (DC) power source and an alternating current (AC) power source. The power connector includes external terminals accessible from an exterior of the vacuum cleaner. The external terminals are configured for removable mechanical connection to each of the DC power source and an AC power supply cord such that the DC power source and the AC power supply cord are selectively and mechanically connectable to the same external power connector terminals.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/620,089, filed Jun. 12, 2017, the disclosure of which is herebyincorporated by reference in its entirety.

FIELD

The field of the disclosure relates generally to vacuum cleaningsystems, and more particularly, to vacuum cleaners operable to run on analternating current (AC) power source and a direct current (DC) powersource.

BACKGROUND

Vacuum cleaners commonly include a motor operable to generate suction tofacilitate removal of dust and/or debris from surfaces. Power may besupplied to the motor, for example, by an alternating current (AC)source (e.g., a wall outlet) or a direct current (DC) source. At leastsome known vacuum cleaners are configured to operate on both an AC powersource and a DC power source. For example, some vacuum cleaners includean AC power cord for connecting the vacuum cleaner to an AC powersource, and a DC battery pack for supplying DC power to the vacuumcleaner.

However, at least some of these vacuum cleaners include currentconverting components, such as inverters or rectifiers, that conditionor otherwise regulate the current supplied to the motor such that thesame type of current (e.g., AC or DC) is supplied to the motorregardless of the power source connected to the vacuum cleaner. Suchcomponents generally increase the cost and complexity of manufacturingvacuum cleaners.

This Background section is intended to introduce the reader to variousaspects of art that may be related to various aspects of the presentdisclosure, which are described and/or claimed below. This discussion isbelieved to be helpful in providing the reader with backgroundinformation to facilitate a better understanding of the various aspectsof the present disclosure. Accordingly, it should be understood thatthese statements are to be read in this light, and not as admissions ofprior art.

SUMMARY

In one aspect, a vacuum cleaner includes a suction inlet, a motor, andan impeller connected to the motor and operable to generate suctionthrough the suction inlet upon operation of the motor. The vacuumcleaner further includes a power connector mounted to the vacuum cleanerand selectively connectable to a direct current (DC) power source and analternating current (AC) power source. The power connector includesexternal terminals accessible from an exterior of the vacuum cleaner.The external terminals are configured for removable mechanicalconnection to each of the DC power source and an AC power supply cordsuch that the DC power source and the AC power supply cord areselectively and mechanically connectable to the same external powerconnector terminals. The power connector is electrically connectable tothe motor via an electrical path such that an AC current is supplied tothe motor when the AC power source is connected to the power connector,and a DC current is supplied to the motor when the DC power source isconnected to the power connector. The electrical path is a commonelectrical path that extends from the power connector to the motor suchthat the AC current and the DC current travel along the same electricalpath from the power connector to the motor regardless of the powersource connected to the power connector.

In another aspect, a vacuum cleaning system includes a suction inlet, amotor, and an impeller connected to the motor and operable to generatesuction through the suction inlet upon operation of the motor. Thevacuum cleaning system further includes a power connector electricallyconnected to the motor for supplying electrical power thereto, a directcurrent (DC) power source selectively connectable to the powerconnector, and a power supply cord having a first end that isselectively connectable to the power connector and a second end thatconnects to an AC power source. The power connector includes externalterminals accessible from an exterior of the vacuum cleaning system. Theexternal terminals are configured for removable mechanical connection toeach of the DC power source and the first end of the power supply cordsuch that the DC power source and the power supply cord are selectivelyand mechanically connectable to the same external power connectorterminals. The power connector is electrically connectable to the motorvia an electrical path such that an AC current is supplied to the motorwhen the AC power source is connected to the power connector, and a DCcurrent is supplied to the motor when the DC power source is connectedto the power connector. The electrical path is a common electrical paththat extends from the power connector to the motor such that the ACcurrent and the DC current travel along the same electrical path fromthe power connector to the motor regardless of the power sourceconnected to the power connector.

Various refinements exist of the features noted in relation to theabove-mentioned aspects. Further features may also be incorporated inthe above-mentioned aspects as well. These refinements and additionalfeatures may exist individually or in any combination. For instance,various features discussed below in relation to any of the illustratedembodiments may be incorporated into any of the above-described aspects,alone or in any combination.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a vacuum cleaning system including avacuum cleaner.

FIG. 2 is a bottom plan view of the vacuum cleaner shown in FIG. 1.

FIG. 3 is an enlarged perspective view of a portion of the vacuumcleaner shown in FIG. 1.

FIG. 4 is a sectional view of the portion of the vacuum cleaner shown inFIG. 3.

FIG. 5 is a side sectional view of the vacuum cleaner shown in FIG. 1.

FIG. 6 is a rear view of the vacuum cleaner shown in FIG. 1.

FIG. 7 is a rear view of the vacuum cleaner shown in FIG. 1 in a cordedmode.

FIG. 8 is a rear view of the vacuum cleaner shown in FIG. 1 in acordless mode.

FIG. 9 is a schematic diagram of the vacuum cleaner shown in FIG. 1.

FIG. 10 is a schematic circuit diagram of the vacuum cleaner shown inFIG. 1 illustrating an electrical connection between an interface of thevacuum cleaner and a motor of the vacuum cleaner.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DETAILED DESCRIPTION

FIG. 1 is a perspective view of an example vacuum cleaning system 100including a vacuum cleaner 102, a battery 104 (generally, a directcurrent (DC) power source), and a power cord 106. In the exampleembodiment, the vacuum cleaner 102 is an upright vacuum cleaner,although aspects of the vacuum cleaning system 100 may be embodied invacuum cleaners other than an upright vacuum cleaner, including withoutlimitation, wet/dry vacuum cleaners, canister vacuum cleaners, andbackpack vacuum cleaners. As described further herein, the vacuumcleaner 102 is operable to run on both DC power supplied by the battery104, and alternating current (AC) power supplied by an AC power source108 (e.g., mains AC electricity from a household or commercial walloutlet) via the power cord 106. Accordingly, the vacuum cleaner 102 maybe operated in a cordless mode, in which the battery 104 is electricallyconnected to the vacuum cleaner 102, and a corded mode, in which thepower cord 106 is electrically connected to the vacuum cleaner 102.

In the example embodiment, the vacuum cleaner 102 generally includes acleaning head 110 and a handle assembly 12 extending upward from andpivotally connected to the cleaning head 110. The cleaning head 110generally includes a housing 114 that houses various components of thevacuum cleaner 102. The handle assembly 112 extends from the cleaninghead 110 to a distal end 116 including a handle 118 that allows a userto maneuver and manipulate the vacuum cleaner 102. In this embodiment,the cleaning head 110 includes a plurality of rollers or wheels 120rotatably connected to the housing 114 to facilitate moving the cleaninghead 110 across a floor or other surface that is cleaned by the vacuumcleaner 102.

FIG. 2 is a bottom view of the vacuum cleaner 102 shown in FIG. 1. Asshown in FIG. 2, the cleaning head 110 has a suction opening 202 definedalong a bottom 204 thereof through which dirt, dust, and/or other debrisare drawn by a vacuum force generated by the vacuum cleaner 102. Thebottom 204 of the cleaning head 110 generally refers to the side orsurface of the cleaning head 110 that faces and/or engages a floor orother surface that is cleaned by the vacuum cleaner 102 in operation.

FIG. 3 is an enlarged perspective view of the vacuum cleaner 102 withthe battery 104 connected, and FIG. 4 is a sectional view of the vacuumcleaner 102. A portion of the cleaning head housing 114 is omitted inFIGS. 3 and 4. As shown in FIGS. 3 and 4, the vacuum cleaner 102includes a motor 302 and a blower or fan 402 (also referred to as animpeller, shown in FIG. 4) connected to the motor 302 by a motor ordrive shaft 304. In this embodiment, the vacuum cleaner 102 alsoincludes a brush unit 306 that includes a rotary brush 404 (FIG. 4)situated directly above the suction opening 202. The rotary brush 404 isoperatively connected to the motor 302 by a belt 308 and pulley 309(FIG. 3), and rotates and contacts the floor or other surface to agitatedebris and promote entrainment of the debris into the airflow drawnthrough the suction opening 202.

The motor 302 is an electric motor that includes a plurality of statorwindings and a rotor (not shown in FIGS. 3 and 4) that rotates inresponse to electrical current being applied to the stator windings. Therotor may include a permanent magnet and/or a plurality of rotorwindings that magnetically interact with the stator windings when acurrent is applied to the rotor and stator windings. The drive shaft 304is operatively connected to the rotor, and rotates in response torotation of the rotor.

The blower 402 is housed within a blower housing 310 in fluidcommunication with the suction opening 202, and is operable to generatesuction through the suction opening 202 upon operation of the motor 302.Air and debris pulled or drawn through the suction opening 202 aredirected through a debris tube 406 (FIG. 4) extending from the blowerhousing 310 and upward from the cleaning head 110. The debris tube 406is pivotally connected to the cleaning head 110, and the handle assembly112 is pivotally connected to the cleaning head 110 by the debris tube406. In this embodiment, the motor 302 and the blower 402 are locatedwithin the cleaning head housing 114. In other embodiments, the motor302 and/or the blower 402 may be located at other locations along thevacuum cleaner 102, such as along or within the handle assembly 112.

As shown in FIG. 5, the vacuum cleaner 102 also includes a filterassembly 502 connected to an outlet 504 of the debris tube 406positioned downstream from the blower 402. The filter assembly 502filters and collects debris from the airstream flowing out of the debristube 406. The filter assembly 502 selectively allows air to pass throughthe filter and retain debris within the filter assembly 502. The filterassembly 502 may include, for example and without limitation, a bagfilter. In this embodiment, the vacuum cleaner 102 does not include anyfilters upstream of the blower 402. Thus, the blower 402 is disposed inan unfiltered or “dirty” airstream or flow path. In some embodiments,such as the embodiment shown in FIG. 5, the filter assembly 502 includesa filter switch 506 that interrupts the power supply to the motor 302when a filter bag is not connected to the outlet 504.

Referring again to FIG. 1, the vacuum cleaner 102 is selectivelyconnectable to the battery 104 and the power cord 106 to supply power tothe vacuum cleaner 102. In this embodiment, the battery 104 is a directcurrent (DC) source battery. That is, the battery 104 is configured tosupply direct current to the vacuum cleaner 102 when the battery 104 isconnected to the vacuum cleaner 102. The battery 104 may have anysuitable DC battery construction that enables the vacuum cleaner 102 tofunction as described herein. For example, the battery 104 may include,without limitation, a lithium-ion battery, a nickel-metal hydridebattery, a lead-acid battery, a lithium-metal battery, a supercapacitoror other capacitor based voltage source, a lithium nickel manganesecobalt oxide battery, a lithium nickel cobalt aluminum oxide battery,and any other suitable DC battery construction that enables the vacuumcleaner 102 to function as described herein. In this embodiment, thebattery 104 is a rechargeable lithium-ion battery. The power cord 106includes a first end 122 that connects to vacuum cleaner 102, and asecond end 124 that connects to the AC power source 108. The power cord106 also includes a suitable electrical conduit extending from the firstend 122 to the second end 124.

With additional reference to FIG. 6, the vacuum cleaner 102 includes anelectrical connection interface 602 for connecting a power source to thevacuum cleaner 102. The electrical connection interface 602 isselectively connectable to both the battery 104 and an AC power source108 via the power cord 106. Specifically, the battery 104 and the powercord 106 have a common connection interface configuration thatcorresponds to the configuration of the electrical connection interface602. In this embodiment, the electrical connection interface 602includes a male IEC connector integrated into the handle assembly 112,and the battery 104 and the power cord 106 (specifically, the first end122 of the power cord 106) each includes a female IEC connector thatinterconnects or mates with the male IEC connector. In otherembodiments, the electrical connection interface 602 may have aconfiguration other than an IEC connector configuration.

FIG. 7 is a rear view of the vacuum cleaner 102 with the power cord 106connected to the electrical connection interface 602, and FIG. 8 is arear view of the vacuum cleaner 102 with the battery 104 connected tothe electrical connection interface 602. As shown in FIGS. 6-8, thepower cord 106 and the battery 104 connect to the same electricalconnection interface 602. Thus, in this embodiment, only one of thepower cord 106 and the battery 104 can be connected to the electricalconnection interface 602 at a time.

In this embodiment, the battery 104 is connected directly to theelectrical connection interface 602, and is secured to the vacuumcleaner 102. Further, in this embodiment, the vacuum cleaner 102includes a battery support plate 604 connected to the handle assembly112 and located proximate the electrical connection interface 602. Thebattery support plate 604 is adapted to releasably support the battery104 on the vacuum cleaner 102 when the battery 104 is connected to theelectrical connection interface 602.

FIG. 9 is a schematic diagram of the vacuum cleaner 102, and FIG. 10 isa schematic circuit diagram illustrating the electrical connectionbetween the electrical connection interface 602 and the motor 302.

As shown in FIGS. 9 and 10, the electrical connection interface 602 iselectrically connected to the motor 302 to supply current to motorwindings 902 (FIG. 9), which may include stator windings and/or rotorwindings. When current is applied to the motor windings 902, the rotor904 rotates, causing the drive shaft 304 to rotate, and thereby rotatethe blower 402 to generate airflow through the suction opening 202 (FIG.2).

The electrical connection interface 602 is electrically connectable tothe motor 302 via at least one electrical path such that an AC currentis supplied to the motor 302 when the AC power source 108 (FIG. 1) isconnected to the electrical connection interface 602, and such that a DCcurrent is supplied to the motor 302 when the battery 104 (FIG. 1) isconnected to the electrical connection interface 602. For example, theelectrical connection interface 602 is connectable to the motor 302along at least one electrical path 1002 (FIG. 10) without anyintervening converters, e.g., inverters (generally, DC to AC converters)or rectifiers (generally, AC to DC converters). Consequently, the typeof current supplied by the power source (e.g., the battery 104 or the ACpower source 108) is the same type of current applied to the motorwindings 902.

Further, the electrical connection interface 602 is connectable to themotor 302 such that DC and AC currents supplied by the battery and ACpower sources, respectively, travel along a common electrical path 1002from the electrical connection interface 602 to the motor 302. Thus,when the battery 104 is connected to the electrical connection interface602, the battery 104 applies a DC voltage across the terminals of theelectrical connection interface 602, and supplies direct current to themotor 302 (specifically, the windings 902 of the motor 302) via theelectrical path 1002. When the power cord 106 is connected to the ACpower source 108 and the electrical connection interface 602, an ACvoltage is applied across the terminals of the electrical connectioninterface 602, and an AC current is supplied to the motor 302(specifically, the windings 902 of the motor 302) via the electricalpath 1002.

Thus, in contrast to at least some known vacuum cleaners, embodiments ofthe vacuum cleaner 102 supply current to the motor 302 along at leastone electrical path along which the current is not converted orregulated to operate the motor 302 on a single type of current. Rather,embodiments of the vacuum cleaner 102 include at least one electricalpath 1002 between the connection interface 602 and the motor 302 that isfree of costly current converting elements, such as inverters andrectifiers, such that the motor 302 operates on the same type of currentas that supplied by the power source connected to the vacuum cleaner102.

In this embodiment, the electrical connection interface 602 is connectedto the motor 302 through a power switch 1004 (FIG. 10) and a controlboard 906. The power switch 1004 is selectively positionable (e.g., by auser) between a plurality of switch positions that connect theconnection interface 602 to the motor 302 along different electricalpaths. In this embodiment, the power switch 1004 is positionable ormovable between a first, high power mode position, a second, low powermode position, and an off position. In the high power mode position, theconnection interface 602 is connected to the motor 302 along a firstelectrical path 1002 that is free of intervening converters, e.g.,inverters (generally, DC to AC converters) and rectifiers (generally, ACto DC converters). Consequently, the type of current supplied to themotor 302 when the power switch is in the high power mode positioncorresponds to the current supplied by the power source (i.e., AC orDC). In the low power mode position, the connection interface 602 isconnected to the motor 302 along a second electrical path 1006 thatincludes a rectifying element 1008 (e.g., a diode) that limits orgoverns the amount of power supplied to the motor 302 when the vacuumcleaner 102 is operating on AC power. Consequently, when the vacuumcleaner 102 is operated in the low power mode on AC power, the motor 302and rotary brush 404 operate at a reduced speed as compared to the highpower mode.

The first and second electrical paths 1002 and 1006 each extend from afirst terminal of the connection interface 602, to the motor 302, andback to a second terminal of the connection interface 602. In thisembodiment, the first and second electrical paths 1002 and 1006 share atleast some common electrical paths. However, as noted above, the firstelectrical path 1002 is free of intervening converters and rectifiersbetween the connection interface 602 and the motor 302, whereas thesecond electrical path 1006 includes the rectifying element 1008 tolimit or govern the amount of power supplied to the motor 302.

In this embodiment, the power switch 1004 includes three switchpositions—the high power mode position, the low power mode position, andthe off position. In other embodiments, the power switch 1004 mayinclude only on and off positions such that the connection interface 602is electrically connectable to the motor 302 via a single electricalpath. In yet other embodiments, the power switch 1004 may include anysuitable number of switch positions that enables the vacuum cleaner 102to function as described herein.

In this embodiment, the control board 906 includes additional componentsfor controlling operation of the vacuum cleaner 102 and providingoperational status feedback to a user. As shown in FIG. 10, for example,the control board 906 includes a motor protection relay 1010, amicrocontroller 1012, and a power supply 1014 for supplying low voltagepower to the relay 1010 and the microcontroller 1012. Themicrocontroller 1012 is configured to actuate the motor protection relay1010 in response to speed signals received from a speed sensor 1016 thatmeasures a rotational speed of the rotary brush 404. In one embodiment,for example, the microcontroller 1012 actuates the relay 1010 todisconnect the motor 302 from a power supply when a detected speed ofthe rotary brush 404 falls below a threshold speed to protect componentsof the vacuum cleaner 102, such as the belt 308, from premature failure.

Additionally, in this embodiment, the control board 906 includes aplurality of operational status light emitting diodes (LEDs) 1018 and aplurality of battery gauge LEDs 1020. The operational status LEDs 1018and the battery gauge LEDs 1020 are connected to the microcontroller1012 and the power supply 1014. The microcontroller 1012 controlsillumination of the operational status LEDs 1018 and the battery gaugeLEDs 1020 based on one more operational parameters of the vacuum cleaner102. For example, the microcontroller 1012 may control illumination ofthe operational status LEDs 1018 to indicate a current operating mode ofthe vacuum cleaner 102, the presence of an error or malfunction, that afilter bag of the vacuum cleaner 102 is full, or any other suitablestatus indicator that enables the vacuum cleaner 102 to function asdescribed herein. In this embodiment, the microcontroller 1012 alsocontrols illumination of the battery gauge LEDs 1020 to indicate a stateof charge or remaining capacity of the battery 104 when the battery 104is connected to the connection interface 602. As shown in FIG. 10, thecontrol board 906 includes a voltage sensor 1022 to detect a state ofcharge of the battery 104.

In some embodiments, the vacuum cleaner 102 includes certain features tofacilitate operation of the motor 302 on both AC and DC power sources.In some embodiments, for example, the motor 302 is a universal motor302. Universal motors generally include a commutated series-wound motorin which stator field coils or windings are connected in series withrotor windings through a commutator. Universal motors are particularlywell suited to operate on both AC and DC current.

Moreover, the motor 302 may have a relatively low current load rating.In some embodiments, for example, the motor 302 has a current loadrating of between 2 amperes and 12 amperes at a voltage of 120 volts,between 3 amperes and 6 amperes at a voltage of 120 volts, or between 3amperes and 5 amperes at a voltage of 120 volts. In some embodiments,the motor 302 has a current load rating of 4 amperes at a voltage of 120volts.

Further, in some embodiments, the battery 104 has an output or operatingvoltage that is comparable to the average RMS voltage of mains ACelectricity supplied to residential households and commercial businesses(i.e., 120 VAC). For example, the battery 104 may have a DC outputvoltage that is within 66% of the average RMS of mains AC voltage,within 33% of the average RMS of mains AC voltage, within 30% of theaverage RMS of mains AC voltage, within 25% of the average RMS of mainsAC voltage, or within 20% of the average RMS of mains AC voltage. Insome embodiments, for example, the battery 104 has a DC output voltageof between 50 volts DC (VDC) and 140 VDC, between 80 VDC and 140 VDC,between 90 VDC and 130 VDC, between 90 VDC and 120 VDC, between 100 VDCand 120 VDC, or between 90 VDC and 110 VDC. In this embodiment, thebattery 104 has an output voltage of 92.4 VDC. Other suitable outputvoltages of the battery 104 include, for example and without limitation,about 80 VDC and about 108 VDC. In other embodiments, the battery 104may have any suitable output voltage that enables the vacuum cleaner 102to function as described herein.

Additionally, in this embodiment, the vacuum cleaner 102 includes acapacitor 1024 electrically connected in parallel with the motor 302 toinhibit or prevent electrical arcing across contacts of switches (e.g.,power switch 1004) of the vacuum cleaner 102. In particular, in thisembodiment, the capacitor 1024 is connected across the terminals of themotor 302 such that energy stored in the motor 302 is dissipated throughthe capacitor 1024 when the vacuum cleaner 102 is shut off.

Embodiments of the vacuum cleaning system 100 may have a relativelylightweight construction as compared to other upright vacuum cleanersthat operate on a high voltage DC battery. In some embodiments, forexample, the vacuum cleaning system 100, including the vacuum cleaner102, the battery 104, and the power cord 106, has a combined or totalweight of less than 25 pounds, less than 20 pounds, less than 18 pounds,less than 16 pounds, and even less than 14 pounds.

Embodiments of the vacuum cleaning systems and vacuum cleaners describedherein achieve superior results as compared to previous vacuum cleaners.For example, embodiments of the vacuum cleaners include an electricalconnection interface that is selectively connectable to both a DC powersource and an AC power source, and that is electrically connectable to amotor of the vacuum cleaner along at least one electrical path such thatthe motor operates on the same type of current as that supplied by thepower source. In embodiments of the present disclosure, the electricalconnection interface is connectable to the motor along an electricalpath without intervening inverters or rectifiers, thereby reducing thecost and complexity of manufacturing the vacuum cleaner as compared tovacuum cleaning systems that include costly current converting elementsor circuitry. Moreover, embodiments of the vacuum cleaners describedherein use a universal motor and a DC power source having an outputvoltage comparable to the output voltage of mains AC power to facilitateefficient operation of the motor on both AC and DC power.

Example embodiments of vacuum cleaning systems and vacuum cleaners aredescribed above in detail. The vacuum cleaning systems and vacuumcleaners are not limited to the specific embodiments described herein,but rather, components of the vacuum cleaning systems and vacuumcleaners may be used independently and separately from other componentsdescribed herein. For example, features of the vacuum cleaning systemsdescribed herein may be used with vacuum cleaners other than uprightvacuum cleaners, including without limitation, wet/dry vacuum cleaners,canister vacuum cleaners, and backpack vacuum cleaners.

When introducing elements of the present disclosure or the embodiment(s)thereof, the articles “a”, “an”, “the” and “said” are intended to meanthat there are one or more of the elements. The terms “comprising,”“including,” “containing” and “having” are intended to be inclusive andmean that there may be additional elements other than the listedelements. The use of terms indicating a particular orientation (e.g.,“top”, “bottom”, “side”, etc.) is for convenience of description anddoes not require any particular orientation of the item described.

As various changes could be made in the above constructions and methodswithout departing from the scope of the disclosure, it is intended thatall matter contained in the above description and shown in theaccompanying drawing(s) shall be interpreted as illustrative and not ina limiting sense.

What is claimed is:
 1. A vacuum cleaner comprising: a suction inlet; amotor; an impeller connected to the motor and operable to generatesuction through the suction inlet upon operation of the motor; and apower connector mounted to the vacuum cleaner and selectivelyconnectable to a direct current (DC) power source and an alternatingcurrent (AC) power source, the power connector including externalterminals accessible from an exterior of the vacuum cleaner, wherein theexternal terminals are configured for removable mechanical connection toeach of the DC power source and an AC power supply cord such that the DCpower source and the AC power supply cord are selectively andmechanically connectable to the same external power connector terminals,wherein the power connector is electrically connectable to the motor viaan electrical path such that an AC current is supplied to the motor whenthe AC power source is connected to the power connector, and a DCcurrent is supplied to the motor when the DC power source is connectedto the power connector, and wherein the electrical path is a commonelectrical path that extends from the power connector to the motor suchthat the AC current and the DC current travel along the same electricalpath from the power connector to the motor regardless of the powersource connected to the power connector.
 2. The vacuum cleaner of claim1 further including the AC power supply cord, wherein the AC powersupply cord has a first end that connects to the power connector and asecond end that connects to the AC power source.
 3. The vacuum cleanerof claim 1, wherein the electrical path is free of intervening invertersand rectifiers between the power connector and the motor such that ACcurrent is supplied to the motor when the AC power source is connectedto the power connector, and DC current is supplied to the motor when theDC power source is connected to the power connector.
 4. The vacuumcleaner of claim 3, wherein the electrical path is a first electricalpath, and wherein the power connector is selectively connectable to themotor via the first electrical path and a second electrical path byoperation of a power switch, wherein the second electrical path includesa rectifying element for low speed AC operation.
 5. The vacuum cleanerof claim 1, wherein the motor includes a plurality of windings, andwherein the power connector is electrically connectable to the motor viathe electrical path such that the AC current is supplied to theplurality of windings when the AC power source is connected to the powerconnector, and the DC current is supplied to the plurality of windingswhen the DC power source is connected to the power connector.
 6. Thevacuum cleaner of claim 1 in combination with the DC power source,wherein the DC power source has a DC output voltage of between 50 voltsand 140 volts.
 7. The vacuum cleaner of claim 1, wherein the motor is auniversal motor.
 8. The vacuum cleaner of claim 1, wherein the motor israted for a current load of between 2 amperes and 12 amperes at 120volts.
 9. The vacuum cleaner of claim 1, wherein the motor is acommutated series-wound motor including stator windings and rotorwindings, wherein the stator windings are connected in series with therotor windings through a single commutator.
 10. The vacuum cleaner ofclaim 1, further comprising a power switch positionable between an offposition and at least one on position to control supply of power to themotor along the electrical path.
 11. The vacuum cleaner of claim 1,wherein the vacuum cleaner is one of an upright vacuum cleaner, awet/dry vacuum cleaner, a canister vacuum cleaner, and a backpack vacuumcleaner.
 12. A vacuum cleaning system comprising: a suction inlet; amotor; an impeller connected to the motor and operable to generatesuction through the suction inlet upon operation of the motor; a powerconnector electrically connected to the motor for supplying electricalpower thereto; a direct current (DC) power source selectivelyconnectable to the power connector; and a power supply cord having afirst end that is selectively connectable to the power connector and asecond end that connects to an AC power source, wherein the powerconnector includes external terminals accessible from an exterior of thevacuum cleaning system, the external terminals configured for removablemechanical connection to each of the DC power source and the first endof the power supply cord such that the DC power source and the powersupply cord are selectively and mechanically connectable to the sameexternal power connector terminals, wherein the power connector iselectrically connectable to the motor via an electrical path such thatan AC current is supplied to the motor when the AC power source isconnected to the power connector, and a DC current is supplied to themotor when the DC power source is connected to the power connector,wherein the electrical path is a common electrical path that extendsfrom the power connector to the motor such that the AC current and theDC current travel along the same electrical path from the powerconnector to the motor regardless of the power source connected to thepower connector.
 13. The vacuum cleaning system of claim 12, wherein theelectrical path is free of intervening inverters and rectifiers betweenthe power connector and the motor such that AC current is supplied tothe motor when the AC power source is connected to the power connector,and DC current is supplied to the motor when the DC power source isconnected to the power connector.
 14. The vacuum cleaning system ofclaim 13, wherein the electrical path is a first electrical path, andwherein the power connector is selectively connectable to the motor viathe first electrical path and a second electrical path by operation of apower switch, wherein the second electrical path includes a rectifyingelement for low speed AC operation.
 15. The vacuum cleaning system ofclaim 12, wherein the motor includes a plurality of windings, andwherein the power connector is electrically connectable to the motor viathe electrical path such that the AC current is supplied to theplurality of windings when the AC power source is connected to the powerconnector, and the DC current is supplied to the plurality of windingswhen the DC power source is connected to the power connector.
 16. Thevacuum cleaning system of claim 12, wherein the DC power source has a DCoutput voltage of between 50 volts and 140 volts.
 17. The vacuumcleaning system of claim 12, wherein the motor is a universal motor. 18.The vacuum cleaning system of claim 12, wherein the motor is acommutated series-wound motor including stator windings and rotorwindings, wherein the stator windings are connected in series with therotor windings through a single commutator.
 19. The vacuum cleaningsystem of claim 12, further comprising a power switch positionablebetween an off position and at least one on position to control supplyof power to the motor along the electrical path.
 20. The vacuum cleaningsystem of claim 12, wherein the vacuum cleaning system is one of anupright vacuum cleaner, a wet/dry vacuum cleaner, a canister vacuumcleaner, and a backpack vacuum cleaner.